Multiple vendors' IPv6 issues

[brak at gameservers.com (Brian Rak)]

On 5/27/2015 3:20 PM, Jared Mauch wrote:
> On Tue, May 26, 2015 at 04:19:25PM -0700, David Sotnick wrote:
>> Hi NANOG,
>>
>> The company I work for has no business case for being on the IPv6-Internet.
>> However, I am an inquisitive person and I am always looking to learn new
>> things, so about 3 years ago I started down the IPv6 path. This was early
>> 2012.
>>
>> Fast forward to today. We have a /44 presence for our company's multiple
>> sites; All our desktop computers have been on the IPv6 Internet since June,
>> 2012 and we have a few AAAAs in our external DNS for some key services ?
>> and, there have been bugs. *Lots* of bugs.
>>
>> Now, maybe (_maybe_) I can have some sympathy for smaller network companies
>> (like Arista Networks at the time) to not quite have their act together as
>> far as IPv6 goes, but for larger, well-established companies to still have
>> critical IPv6 bugs is just inexcusable!
> 	My current favorites are:
>
> https://tools.cisco.com/bugsearch/bug/CSCut62344
>
> Which doesn't allow you to see the neighbors on an interface.  this is fun
> when diagnosing qemu/kvm issues with the macvtap and hosts with ipv6.
> turns out you to 'fix it' you need to make the macvtap interface promisc
> as the icmpv6 messages don't make it through the macvtap driver to the VM
> breaking neighbor discovery.
You don't need full promisc mode, just the (poorly documented) 
allmulticast option (ip link set dev $macvtap allmulticast on)